Original Research Paper
Network Security
M. Amiri; A. Barati
Articles in Press, Corrected Proof, Available Online from 01 November 2019
Abstract
Increasing usage of Internet and computer networks by individuals and organizations and also attackers’ usage of new methods and tools in an attempt to endanger network security, have led to the emergence of a wide range of threats to networks. A honeypot is one of the basic techniques employed ...
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Increasing usage of Internet and computer networks by individuals and organizations and also attackers’ usage of new methods and tools in an attempt to endanger network security, have led to the emergence of a wide range of threats to networks. A honeypot is one of the basic techniques employed for network security improvement. It is basically designed to be attacked so as to get the attackers’ information and trap them. By using a vulnerable scanner in this paper, we obtained the required network vulnerabilities and normalized them via the proposed method. Then, a dynamic hybrid honeypot has proposed by high and low interaction honeypots. Also, in the proposed method, by footprinting and scanning of an integrated network, a detailed picture of the production network and a honeypot configuration file are generated. As a result, more devices could be detected via automated production by the proposed method. This method could accelerate honeypot production and reduce the users’ mistakes during their manual production. Monitoring network traffic, collecting the information of network machines, determining network operating systems, and storing data in a database are the specific features of this system that could be performed by using the selected network scanning tools and modules.
Original Research Paper
Control
H. Chenarani; M.M. Fateh
Articles in Press, Corrected Proof, Available Online from 01 November 2019
Abstract
This paper presents a robust passivity-based voltage controller (PBVC) for robot manipulators with n degree of freedom in the presence of model uncertainties and external disturbance. The suggested controller inherits both advantages of the passivity-based control (PBC) scheme and voltage control strategy ...
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This paper presents a robust passivity-based voltage controller (PBVC) for robot manipulators with n degree of freedom in the presence of model uncertainties and external disturbance. The suggested controller inherits both advantages of the passivity-based control (PBC) scheme and voltage control strategy (VCS). Since the proposed control approach only uses the electrical model of the actuators, the obtained control law is simple and also has an independent-joint structure. Moreover, the proposed PBVC overcomes the drawbacks of torque control strategy such as the complexity of manipulator dynamics, practical problems and ignoring the role of actuators. Generally, the controller design procedure is divided into two steps. First, a model-based controller is designed based on the PBC scheme. An output feedback law is suggested to ensure the asymptotic stability of the closed-loop error dynamics. Second, a regressor-free adaptation law is obtained to estimate the variations of the model uncertainties and external disturbance. The proposed control law is provided in two different orders. Moreover, computer simulations are carried out for both tracking and regulation purposes. In addition, the proposed controller is compared with a passivity-based torque controller where the simulation results show the appropriate efficiency of the proposed approach.
Original Research Paper
Electronics
Z. Kordrostami; S. Hamedi; F. Khalifeh
Articles in Press, Corrected Proof, Available Online from 01 November 2019
Abstract
In this paper, two developed designs of InGaAs/InAlAs high electron mobility transistors (HEMTs) have been studied. The proposed laterally contacted HEMTs satisfy the desired high frequency characteristics and are good candidates for high frequency applications. Two kinds of HEMTs have been designed ...
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In this paper, two developed designs of InGaAs/InAlAs high electron mobility transistors (HEMTs) have been studied. The proposed laterally contacted HEMTs satisfy the desired high frequency characteristics and are good candidates for high frequency applications. Two kinds of HEMTs have been designed and simulated: single-gate laterally contacted HEMT (SGLC-HEMT) and double-gate laterally contacted HEMT (DGLC-HEMT). The proposed SGLC-HEMT exhibits 111 GHz current-gain cut-off frequency. By using double-gate design, the current-gain cut-off frequency has been increased to 256 GHz. The simulation results show that the maximum oscillation frequency for the proposed SGLC and DGLC HEMTs, are 410 GHz and 768 GHz, respectively. Maximum value of transconductance (gm) for SGLC-HEMT is obtained 620 mS/mm while it is 1130 mS/mm for DGLC-HEMT.
Original Research Paper
Control
M. Siavash; V. Majd; M. Tahmasebi
Articles in Press, Corrected Proof, Available Online from 01 November 2019
Abstract
This article discusses a finite-time fault-tolerant consensus control for stochastic Euler-Lagrange multi-agent systems. First, the finite-time consensus controller of Euler-Lagrange multi-agent systems with stochastic disturbances is presented. Then, the proposed controller is extended as a fault-tolerant ...
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This article discusses a finite-time fault-tolerant consensus control for stochastic Euler-Lagrange multi-agent systems. First, the finite-time consensus controller of Euler-Lagrange multi-agent systems with stochastic disturbances is presented. Then, the proposed controller is extended as a fault-tolerant controller in the presence of faults in the actuators. In these two cases, the sliding-mode distributed consensus controllers are designed. The results guarantee that by using these controllers, the consensus tracking errors converge to a desired area near the origin in finite-time with the mean-square sense and also remain bounded in probability. In the simulation section, a robotic manipulator model with actuator faults and stochastic disturbances is discussed and the suggested consensus controller has been used for this case study.
Original Research Paper
Electronics
A. Mouri Zadeh Khaki; E. Farshidi
Articles in Press, Accepted Manuscript, Available Online from 30 April 2020
Abstract
In this paper, a novel continuous-time 1-1 MASH ∆∑ Time-to-digital converter (TDC) is presented. Since the proposed design utilizes 12-bit quantizer based on Gated Switched-Ring Oscillator (GSRO) for both stages, it has been implemented all-digitally. By using a novel structure, only one multi-bit ...
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In this paper, a novel continuous-time 1-1 MASH ∆∑ Time-to-digital converter (TDC) is presented. Since the proposed design utilizes 12-bit quantizer based on Gated Switched-Ring Oscillator (GSRO) for both stages, it has been implemented all-digitally. By using a novel structure, only one multi-bit counter is employed for both stages, therefore the required hardware for implementation of this work is much less than conventional TDCs. As a result, complexity, chip area and power consumption would decrease considerably. We implemented the proposed design prototype on an Altera Stratix IV FPGA board. Measured results demonstrate that although this work uses less complex architecture in comparison with previous works, it provides appropriate performance such as 60.7 dB SNR within 8 MHz signal bandwidth at 400 MHz sampling rate while consuming 2.79 mW that reveals suitability of the proposed TDC to be incorporated in fast and accurate applications such as ADPLLs and high-resolution photoacoustic tomography.
Original Research Paper
Hardware
H. Khanmirza; A. Oloomi
Articles in Press, Accepted Manuscript, Available Online from 11 May 2020
Abstract
Nowadays, video hosting services receive and stream videos using standard protocols like Real-Time Messaging Protocol (RTMP). During the streaming process, video file streams are usually divided into small multi-second parts, and the player receives these parts instead of the whole file at once. Most ...
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Nowadays, video hosting services receive and stream videos using standard protocols like Real-Time Messaging Protocol (RTMP). During the streaming process, video file streams are usually divided into small multi-second parts, and the player receives these parts instead of the whole file at once. Most of the streaming protocols are capable of adaptive streaming and tolerating faults like device failures, and link disconnections. Faults might affect the performance of live streaming in terms of packet loss, latency, jitter, and video quality. The software-defined networking (SDN) paradigm has also gained momentum in enterprise networks due to its lower-cost management and better network utilization. However, full migration from the current networks to the SDN model is not practical. The purpose of this study is to investigate the effectiveness of fault tolerance mechanisms of RTMP protocol on hybrid SDNs. In this paper, a practical and straightforward hybrid network architecture is proposed for gradual migration from traditional IP networks. Then, the performance of the RTMP protocol is tested for live video streaming on this network in the face of various faults. The results obtained from different experiments with different streams facing multiple failures show that the proposed network performs better in restoring RTMP streams compared to traditional networks.
Original Research Paper
Communications
M. Sheikh-Hosseini
Articles in Press, Accepted Manuscript, Available Online from 11 May 2020
Abstract
This paper investigates multiuser detection for space-time block coded (STBC) transmission over a flat-fading multiple-input multiple-output multiple-access channel consisting of J co-channel users each with N antennas and a zero-forcing coherent receiver equipping with M receiving antennas. For the ...
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This paper investigates multiuser detection for space-time block coded (STBC) transmission over a flat-fading multiple-input multiple-output multiple-access channel consisting of J co-channel users each with N antennas and a zero-forcing coherent receiver equipping with M receiving antennas. For the cases in which M=J , it was previously claimed that it is impossible to extend this receiver to general scenarios of orthogonal STBC transmission with J>2 and N>2 . This paper provides a theorem allowing this extension to any scenarios satisfying the theorem condition. Describing in more details, we first prove that zero-forcing receiver of M=J antennas can successfully extend to any STBC transmission over MIMO multiple-access systems which provides an Alamouti-like structure for the inner product of equivalent channels between different receive antennas and users. Then, in order to gain more insight, the theorem role on extending zero-forcing receiver to transmission of orthogonal STBC over MIMO multiple-access systems with J>2 and N>2 , and also to other STBC schemes like generalized coordinate interleaved orthogonal design and Quasi-orthogonal STBC is investigated in more details. Finally, the average symbol error rate of considered scenarios are numerically evaluated and compered for different STBC schemes with various numbers of J and N.
Original Research Paper
Image Processing
A. Sharifi
Articles in Press, Accepted Manuscript, Available Online from 11 May 2020
Abstract
High resolution multi-spectral (HRMS) images are essential for most of the practical remote sensing applications. Pansharpening is an effective mechanism to produce HRMS image by integrating the significant structural details of panchromatic (PAN) image and rich spectral features of multi-spectral (MS) ...
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High resolution multi-spectral (HRMS) images are essential for most of the practical remote sensing applications. Pansharpening is an effective mechanism to produce HRMS image by integrating the significant structural details of panchromatic (PAN) image and rich spectral features of multi-spectral (MS) images. The traditional pansharpening methods incur disadvantages like spectral distortion, spatial artifacts and lack of details preservation in the fused image. The pansharpening approach proposed in this paper is based on integrating wavelet decomposition and convolutional sparse representation (CSR). The wavelet decomposition is performed on PAN and MS images to obtain low-frequency and high-frequency bands. The low-frequency bands are fused by exploring the CSR based activity level measurement while the high-frequency bands are fused based on the constituent wavelet energy. Finally, the HRMS image is restored by implementing the inverse transform on fused bands. The fusion rules are constructed, thus to transfer the crucial details from source images to the fused image effectively. The proposed method produces HRMS images with rational spatial and spectral qualities at relatively less computational effort compared with most of the traditional sparse representation methods. The visual outcomes and quantitative measures approve the eminence of the proposed fusion framework.
Original Research Paper
Control of Biological Systems
Mohammad Mohammadian
Articles in Press, Accepted Manuscript, Available Online from 04 June 2020
Abstract
Regulation of protein expression in cellular level are so challenging. In cellular scale, biochemical processes are intrinsically noisy and many convenient controllers aren’t physically implementable. This paper deals with the design of implementable controller for stochastic gene regulatory networks ...
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Regulation of protein expression in cellular level are so challenging. In cellular scale, biochemical processes are intrinsically noisy and many convenient controllers aren’t physically implementable. This paper deals with the design of implementable controller for stochastic gene regulatory networks with multiplicative and additive noises. In particular, we consider structural limitations that are present in real cellular systems and design the decentralized feedback that guarantees noise to state stability. To do this end, we consider standard Lyapunov function and by using Ito formula and stochastic analysis, we derive sufficient conditions for noise to state stability presented in the form of matrix inequalities. In the next step, by defining appropriate change of variables, matrix inequalities are transformed to Linear matrix inequalities which can be used to synthesize controller with the desired structure. Since the proposed conditions for controller design are in the form of linear matrix inequalities, controller gains can be derived efficiently through solving presented LMIs numerically. It is noteworthy that Because of its simple structure, the proposed controller can be implemented universally in many cells. Finally, we consider a synthetic gene regulatory network and investigate the effectiveness of the proposed controller by simulations.
Original Research Paper
Power
Babak Ganji; Ehsan Limuchi; Abas Taher
Articles in Press, Accepted Manuscript, Available Online from 07 June 2020
Abstract
The microgrid voltage and frequency are strongly affected by active and reactive load fluctuations. Load change in microgrid may result in the lack of balance among generation and consumption and as result change in output voltage and frequency. If load change is great enough, distribution generation ...
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The microgrid voltage and frequency are strongly affected by active and reactive load fluctuations. Load change in microgrid may result in the lack of balance among generation and consumption and as result change in output voltage and frequency. If load change is great enough, distribution generation cannot stabilize the microgrid. The main objective of this article is to control the distribution of active and reactive power related to an inverter-based distributed generation (DG) in the microgrid using intelligent methods. In this study, frequency and voltage of an active generator connected to the microgrid is also controlled with applying adaptive the fuzzy sliding mode control (AFSMC) and the droop control methods. To solve the problems related to design of the sliding mode controller, a compensator control system is suggested. A rule based on the Lyapunov stability theory is also introduced to ensure the stability of closed loop system. The provided simulation results by MATLAB/SIMULINIK software show the effectiveness of suggested method to regulate active and reactive power and to control voltage and frequency of the microgrid.
Original Research Paper
Communications
Negin Danesh; Mansour Sheikhan; Behrad Mahboobi
Articles in Press, Accepted Manuscript, Available Online from 21 June 2020
Abstract
To achieve significant throughput, interference alignment (IA) is an encouraging technique for wireless interference networks. In this study, we design an aligned beamformer based on the interference leakage minimization (ILM) method to reduce the interference power for a multiple-input multiple-output ...
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To achieve significant throughput, interference alignment (IA) is an encouraging technique for wireless interference networks. In this study, we design an aligned beamformer based on the interference leakage minimization (ILM) method to reduce the interference power for a multiple-input multiple-output interference channel (MIMO-IC). To deal with the non-convexity of ILM problem, we used a non-convex programming method (i.e., difference of convex [DC]). In this way, the interference leakage function is reformulated to a DC function including difference of two convex terms. Then, an additive function is defined that includes the DC objective function and a penalty function. We propose a novel DC-based IA algorithm that uses solutions of an upper bound of the additive function in each iteration; as the initial state for the next iteration. Through an iterative manner and for the large values of the penalty factor, the solutions of upper bound function converge to the solutions of the original DC objective function (i.e., interference leakage function). In contrast to the frequent IA methods, the proposed DC-based IA algorithm updates transmit- and receive-beamformers in each iteration jointly (not alternately). Simulation results indicate that the proposed method outperforms some competitive IA algorithms by providing more throughputs and less interference leakage.
Original Research Paper
Control
Ahmad Mirzaei; Amin Ramezani
Articles in Press, Accepted Manuscript, Available Online from 30 July 2020
Abstract
Background and Objectives: In this paper, a constrained cooperative distributed model predictive control (DMPC) is proposed. The proposed DMPC is based on linear adaptive generalized predictive control (AGPC) to control uncertain nonlinear large-scale systems. Methods: The proposed approach, has two ...
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Background and Objectives: In this paper, a constrained cooperative distributed model predictive control (DMPC) is proposed. The proposed DMPC is based on linear adaptive generalized predictive control (AGPC) to control uncertain nonlinear large-scale systems. Methods: The proposed approach, has two main contributions. First, a novel cooperative optimization strategy is proposed to improve the centralized global cost function of each local controller. Second, using the proposed linear distributed AGPC (DAGPC), the mismatch between linearized and nonlinear models is compensated via online identification of the linearized model in each iteration of optimization. Results: The proposed novel cooperative optimization strategy decreases the computational burden of optimization process compared to conventional cooperative DMPC strategies. Moreover, the proposed linear DAGPC decreases the satisfaction time of the terminal condition compared to conventional DMPC methods. The paper establishes sufficient conditions for the closed-loop stability. The performance and effectiveness of proposed method is demonstrated through simulation of a quadruple-tank system for both certain and uncertain situations. The imposed uncertainty changes the system from minimum phase to nonminimum-phase situation. Closed-loop stability and proper convergences are concluded from simulation results of both situations. Conclusion: Most important advantages of proposed linear cooperative DAGPC are its less design complexity and consequently less convergence time compared to fully nonlinear DMPC methods, due to its online identification of the linearized model.
Original Research Paper
Optoelectronics and Photonics
Fariborz Parandin; Mohamadreza Malmir
Articles in Press, Accepted Manuscript, Available Online from 02 August 2020
Abstract
Background and Objectives: Recently, photonic crystals have been considered as the basic structures for the realization of various optical devices for high speed optical communication. Methods: In this research, two dimensional photonic crystals are used for designing all optical logic gates. A photonic ...
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Background and Objectives: Recently, photonic crystals have been considered as the basic structures for the realization of various optical devices for high speed optical communication. Methods: In this research, two dimensional photonic crystals are used for designing all optical logic gates. A photonic crystal structure with a triangular lattice is proposed for making NAND, XNOR, and OR optical logic gates. Using the structure as the intended logic gate is possible without the need to change the structure through the use of the phase difference at the inputs. Line and point defects have been used to propagate light from inputs to output. The logical values "0" and "1", are defined based on the amount of transferred optical power to the output. Results: The simple structure and the use of line and point defects, instead of ring resonators, reduce the complexity of the design and its use in optical logic integrated circuits. Another advantage of proposed structure, in comparison to the previous structures is the reduction in delay time that increases its speed. The maximum delay time of the proposed optical NAND, XNOR, and OR gates is about 0.1 ps. Conclusion: In this study, one structure is suggested for realizing NAND, XNOR, and OR logic gates. This structure has a small size and low time delay, and is suitable for use in optical integrated circuits.
